Search

Due to the influence of environment and other factors, there are often abnormal data in dam monitoring data and the detection of abnormal data plays an indispensable role in the normal operation of the dam. However, the accuracy of traditional anomaly detection algorithms for dam monitoring data often fails to meet the requirements. In this paper, an anomaly detection algorithm based on Prophet GMM was proposed. The better fitting performance of Prophet algorithm was used to fit the dam data and the residual sequence was obtained from the fitting data and the actual data. Then, the residual sequence was clustered by GMM algorithm to accurately identify the abnormal value. The test results show that the method proposed in this paper can accurately identify outliers for different types of dam monitoring data. Compared with the traditional detection algorithm, it has significantly improved the detection indicators of precision, recall and accuracy. [ABSTRACT FROM AUTHOR]

In order to improve the feasibility and comprehensiveness of the application of BIM lightweight technology in water conservancy projects, this paper analyzed and summarized the mainstream BIM lightweight technology. Taking Miyun reservoir reconstruction and elimination of hazards project as an example, it put forward the application route of water conservancy project BIM lightweight technology, and improved the application effects of BIM lightweight technology in different construction stages. In the design stage, the comprehensive use of model reduction optimization, rendering optimization and BIM lightweight collaborative design platform can greatly improve the efficiency of three-dimensional model design; By using the BIM lightweight engine to transmit the BIM design model to the construction stage and establishing a BIM lightweight construction management platform, the quality of construction management can be effectively improved, ensuring that the project is completed on time and with quality. For the current status of BIM lightweight technology, this paper puts forward suggestions for future development: BIM lightweight technology should be able to integrate a variety of water conservancy engineering industry characteristics of data, improve the BIM specifications and standards, so that the BIM lightweight application system is more standardized and scientific. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the assessment method of urban water resources vulnerability too subjective and not taking into account the finite rationality of natural person and the psychological behavior characteristics of regret avoidance, which resulting in the distortion of the evaluation results, this paper proposed an urban water resources vulnerability assessment method based on OWA operator empowerment and regret theory. The DPSIR model was used to construct 29 evaluation indexes from the following five aspects including driving force, pressure, state, influence and response. OWA operator was used to reorder the decision data, which fully considered the location and size of data, so as to weaken the negative effect of extreme decision data on weight. The difference between the utility value of decision data and the ideal utility value in the regret theory was selected as the basis to evaluate the subjectivity of experts, so as to realize the objectification of the subjective data of decision making and improve the objectivity of the evaluation results. Finally, this paper evaluated the water resources vulnerability of Zhengzhou from 2017 to 2022, and compared the evaluation results with those of AHP and regret theory, OWA operator and fuzzy mathematics. The results show that the evaluation results of urban water resources vulnerability assessment method based on OWA operator empowerment and regret theory are basically consistent with the evaluation results of other methods, all of which are considered as severely vulnerable water resources in Zhengzhou City. However, the evaluation results of this method have less relative error and are more close to the actual situation, which can be better used for the assessment of urban water resources vulnerability. [ABSTRACT FROM AUTHOR]

The planting structure and spatial distribution of crops are the basis for the estimation of crop losses in flood disasters. In order to meet the accuracy requirements for rapid assessment of crop losses in flood disasters, it is urgent to build a real-time crop survey and disaster assessment method that combines remote sensing technology with ground surveys. Taking the rainstorm and flood disaster in Henan Province in 2021 as an example, this paper comprehensively used satellite remote sensing data and real ground object sample data obtained from field research to carry out a research on the fine classification of crops in Weihui City, Xinxiang, Henan Province, combined with the flood inundation duration calculation results based on remote sensing data, to assess the damage of crops in this flood disaster event in Weihui City. The results show that: a) The main types of flood disasters in Weihui City are high water level intrusion floods in rivers and waterlogging and stagnation in low-lying areas. b) The types of disaster-affected features are corn, the main crops, green forests around roads, and urban areas of Weihui City. The disaster assessment method for flood crops based on multi-source remote sensing data and real ground object samples proposed in this paper has high accuracy and timeliness. [ABSTRACT FROM AUTHOR]

The Yangtze River Economic Belt is the leading demonstration belt for ecological civilization building. It is of great significance for the sustainable development of regional ecological environment to explore the temporal and spatial changes of ecosystem services and the trade-off/synergy relationships. Based on methods such as land use transfer matrix, modified equivalent factor method, sensitivity index, spatial autocorrelation and Pearson correlation coefficient, this paper quantitatively analyzed the land use situation and its spatial-temporal response to ecosystem services in the Yangtze River Economic Belt from 2000 to 2020, and explored the trade-off/synergistic relationship between various ecosystem services. The results show that during the study period, the land use types in the Yangtze River Economic Belt are mainly forest land, cultivated land and grassland, and the largest area transferred out and transferred into area are cultivated land and forest land respectively. The ecosystem service value of the Yangtze River Economic Belt increases from 7 019.501 billion Yuan in 2000 to 7 042.623 billion Yuan in 2020, with a growth rate of 0.33%. Ecosystem services are mainly hydrological regulation, climate regulation, soil conservation and gas regulation services. The spatial distribution pattern of ecosystem service value in the Yangtze River Economic Belt is as follows: upstream > middle reaches > downstream. The agglomeration effect of the spatial distribution of ecosystem service value in the study area is significant, with high-high agglomeration areas concentrated in upstream areas, low-low agglomeration areas concentrated in downstream Jiangsu Province and Anhui Province, and low-high agglomeration areas concentrated in Panzhihua City, Sichuan Province. The synergy relationship is the dominant relationship of ecosystem services in the Yangtze River Economic Belt, with a synergy rate of 63.64%. [ABSTRACT FROM AUTHOR]

In order to reduce the risk of water shortage of Qinhe River Basin, this paper took Qinhe River Basin as the research object, estimated the blue and green water resources in Qinhe River Basin from 2010 to 2016 based on the output results of the SWAT model, calculated the blue and green water scarcity index through the blue and green water footprint and the blue and green water availability, and quantitatively evaluated the blue and green water shortage situation in Qinhe River Basin by dividing four risk levels of blue and green water shortage. The results show that: a) The average annual blue water resources in Qinhe River Basin are 910 million m³, accounting for 12.0% of the total water resources, and the average annual green water resources are 6.69 billion m³, accounting for 88.0% of the total water resources, and the main component of water resources in Qinhe River Basin is green water resources; b) Under the annual scale, the blue water shortage index of most molecular basins in Qinhe River is greater than 1.0, and the risk level of blue water shortage is relatively serious risk, especially in Jiaozuo City in the downstream area; c) Under the annual scale, the index of green water scarcity in each subbasin of Qinhe River shows some differences, the average annual green water shortage index in most sub-basins is in the range of 0.5-1.0, and the green water shortage faces moderate risk; On the whole, the risk level of green water shortage is lower than that of blue water shortage. Based on the analysis of water shortage indexes of blue water and green water, it put forward suggestions on reducing the water safety risk of Qinhe River Basin. [ABSTRACT FROM AUTHOR]

Evaporation is an essential link between surface energy balance and water balance, and high-cold regions are sensitive to climate change. However, there is a large amount of uncertainty in the evaporation prediction process in the high-cold areas, which poses severe challenges to scientifically analyzing the hydrological cycle changes and water resources management in river basins. Therefore, taking the source area of the Yellow River in the “high-cold region” as an example, this paper used five evaporation calculation models with different physical mechanisms (P-M, Har, J-H, Mak and P-T) to clarify the impact of model uncertainty on the prediction of potential evaporation in the basin. Secondly, by coupling the “evaporation calculation model, GCMs and RCPs” model, the impact of various uncertainties on the uncertainty of potential evaporation prediction in different future periods (short-term, medium-term, and long-term) was explored. The contribution of their independent and interactive effects to the uncertainty of potential evaporation prediction was separated using the variance analysis method. The results show that the potential evaporation model based on solar radiation and temperature is significantly greater than the potential evaporation model based on physical mechanism, and its annual potential evaporation difference is about 150 mm. The uncertainty of RCPs is the main factor leading to the uncertainty of evaporation prediction, accounting for about 65%, and the contribution of the interaction between multiple uncertainty sources to the uncertainty of evaporation prediction is particularly prominent in the “spring and winter” seasons. [ABSTRACT FROM AUTHOR]

Under the rapid urbanization and industrialization, the risk of natural disasters in cities is increasingly exposed, especially the issue of rain-induced flood has become increasingly prominent. In view of the rain-induced flood that has occurred in Gongyi City in recent years, a study on the risk of rain-induced flood in Gongyi City has been carried out in order to provide a scientific basis for the city's disaster prevention and mitigation work. Based on the natural disaster risk assessment theory, this paper built a rain-induced flood risk model with the risk of disaster factors, the risk of disaster-pregnant environment, the vulnerability of disaster-bearing bodies and the ability to prevent and reduce disasters as evaluation indicators. Starting from the above, a total of 14 index factors were selected for quantitative analysis, and the SCS model (Soil Conservation Service) and GIS spatial analysis functions were used to finally obtain the comprehensive risk zoning map of rain and flood disasters in Gongyi City. The results show that Mihe Town, Huiguo Town, Zhitian Town and Xiaoyi Sub-District of Gongyi City are more dangerous. The risk of pregnancy in disaster environment in the north, west and east areas include Heluo Town, Xiaoyi Sub-District, Huiguo Town, Zhitian Town and Mihe Town is higher. The disaster-bearing bodies in the western and central parts are more vulnerable, including Huiguo Town, Zhitian Town and Zhanjie Town. The overall disaster prevention and mitigation capacity of the north is strong, including Zhanjie Town and Zijing Sub-District. In general, the overall risk level of rain-induced flood in Gongyi City is relatively higher, and the high-risk areas are mainly distributed in a belt-like structure in the north-central and western regions. [ABSTRACT FROM AUTHOR]

In order to provide decision-making reference for promoting coordinative development of economy and ecology in the Yellow River Basin, this paper selected panel data from 2010 to 2020, built an indicator system from five levels of growth quality, resources consumption, environmental governance, social life, and scientific research and innovation, used the entropy weight comprehensive index method to evaluate the green development level of the upper reaches of the Yellow River and its four provinces and regions, and analyzed the temporal characteristics and regional differences of the green development level. The results show that from the perspective of temporal variation, the green development level of the upper reaches of the Yellow River has increased steadily since 2010, and by 2020, the criteria level scores are social life, resources consumption, scientific research innovation, growth quality and environmental governance. From the perspective of regional differences, the green development level of the four provinces and regions in the upper reaches of the Yellow River shows a stable and positive trend from 2010 to 2020, but there is still room for improvement. Inner Mongolia scores the highest (0.538) and Qinghai scores the lowest (0.346). From the perspective of internal differences, the weakness of green development in Inner Mongolia is the high consumption of resources. The level of social life and resources consumption in Ningxia needs to be improved. The quality of growth in Gansu is not high. Qinghai needs to improve the level of social life, scientific research innovation and environmental governance. Therefore, the upper Yellow River region should strengthen the quality of growth and environmental governance, implement differentiated measures to improve the level of green development and promote green transformation. [ABSTRACT FROM AUTHOR]

This paper aimed to realize the accurate prediction of the daily reference crop water requirement of the water storage pit irrigation apple orchard based on the limited meteorological data. According to the data of daily temperature and humidity data of the water storage pit irrigation orchard at the Institute of Shanxi Academy of Agricultural Sciences, an ET0 prediction model based on radial basis neural network was built. The simulation results and the calculation results of the two commonly used ET0 calculation formulas of Hargreaves and Priestley-Taylor were compared with the standard values calculated by the FAO-PM formula. The results show that the simulation results of the radial basis neural network model are closer to the standard values calculated by the FAO-PM formula. The calculation results of the Hargreaves formula and the Priestley-Taylor formula are larger than that of the standard values, which should be corrected by coefficients in practical applications. [ABSTRACT FROM AUTHOR]

The intake tower of diversion tunnel of Dongzhuang Hydro-Junction Project is huge, with the largest tower height of 61.5 m, the width of tower body of 26.5 m, the length of downstream flow direction of 26 m, and the maximum designed flow of 5 300 m³/s. The bank slope where the tower is located is steep, so it is necessary to study the dynamic characteristics of the tower. In order to ensure the safety and economy of the intake tower, in this paper, the response spectrum method was used to study the dynamic characteristics of the intake tower under earthquake action, and systematically studied the influence of the height of backfill concrete behind the intake tower on the natural frequency, deformation and stress of the intake tower. The calculation results indicate that when the concrete backfill ratio behind the tower is around 0.80, it can not only meet the safety requirements of the intake tower structure, but also meet the economic conditions. [ABSTRACT FROM AUTHOR]

Dam-break risk standards are the basis for dam managers to make risk decisions. However, as one of the important contents of dam break risk standard, there is no unified environmental risk standard at present. This paper used the research ideas of ecosystem service value and equivalent factor method in ecological economics for reference, and quantified the environmental value. ALARP criterion and F-N curve were used to effectively link environmental standards with existing standards. Considering the differences of environment and economy in different regions of China, the risk preference matrix was built, and the risk preference of each region was determined, so as to formulate the environmental risk standard in China. Taking Luhun Reservoir in Henan Province as an example, the application of this method was illustrated. [ABSTRACT FROM AUTHOR]

In order to improve the deterioration of water quality caused by seasonal water temperature stratification in reservoirs and lakes, this paper was focused on exploring the characteristics of the internal wave induced by the underwater landslide movement and the damage characteristics of water stratification structure by artificially induced internal waves through the disturbance of underwater landslide. The results show that a)the stratification of the water destroyed by the underwater landslide is mainly caused by the disturbance of the upper and lower layers, and the effect of the internal wave is lasting and slow; b) The slope of the landslide and the motion speed of landslide have an important impact on the damaging effects of stratified water; c) The scale of internal waves generated by a landslide at an angle of 45 degrees is greater than that generated by a landslide at an angle of 60 degrees. [ABSTRACT FROM AUTHOR]

In order to quantify trade-associated virtual water flows and evaluate their impact on regional water systems, this paper used the multi-region input-output model to reveal the pattern and structure of the virtual water trade inside and outsided of the Yellow River Basin in 2012,2015 and 2017 and used LMDI method to analyze the impact of the virtual water net output of the watershed relative to others, and used the QAP model to analyze the impact factors of the virtual water trade among provinces within the watershed. The results show that a) the Yellow River Basin as a whole presents a virtual water net input state, but the Yellow River Basin net exports virtual water to Beijing, Tianjin, Hebei and other 12 regions. b) The virtual water trade export industry is mainly the production and supply of agriculture, electricity, gas and water. c) Structure effect and intensity effect are important driving factors of virtual water net output in the watershed. d) QAP regression outcomes prove that economic development level, geographic distance and water use intensity differences are the main factors affecting the virtual water trade. [ABSTRACT FROM AUTHOR]

In order to assess the water resources carrying capacity of the Gansu section of the Yellow River Basin, this paper chose a set of 20 evaluation indicators initially, targeting four distinct secondary regions. Through an analytical process involving sensitivity and correlation assessments, seven indicators that exhibited low sensitivity and high correlation were pruned, culminating in a refined set of 13 indicators. These indicators were systematically organized into four sub-systems of water resources, societal factors, economic aspects, and ecological environment. The composite scores were derived by integrating the entropy weight method with the TOPSIS model. Furthermore, a barrier factor diagnosis model was applied to evaluate the water resources carrying capacity across the four secondary regions. The findings reveal spatial variations in carrying capacity, with the area above Longyangxia station demonstrating the highest capacity, followed by the sections from Longyangxia station to Lanzhou and from Lanzhou to Hekouzhen station, and the lowest capacity observed in the section from Longmen to Sanmenxia station. In terms of temporal trends, barring the area above Longyangxia station, a steady rise in carrying capacity is observed in the remaining three regions. Key factors impeding the water resources carrying capacity in the Gansu section of the Yellow River Basin encompass per capita water availability, water production index, per capita water supply, population density, urbanization rate, and the rate of water usage for ecological environments. Strategic planning of water resources distribution, restructuring water consumption patterns, and synchronizing water resources carrying capacity with economic growth are instrumental in enhancing and sustaining the carrying capacity of the Gansu section of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

Based on the daily precipitation data of 15 ground stations in the source regions of the Yellow River, the daily runoff data of Tangnaihai Hydrological Station and the wavelet analysis method, this paper analyzed the periodic law, change trend and correlation of precipitation and runoff in the flood season of the source regions of the Yellow River from 1961 to 2020. The results show that a) the precipitation and runoff in the flood season of the source regions of the Yellow River in the past 60 years have the characteristics of multi-time scales, and the variation trends of precipitation and runoff in flood season are different at different time scales. b) The precipitation and runoff series in flood season have the main periods of about 63 years and about 35 years, and the average periods of the three time scales are about 41 years and 25 years, respectively. The precipitation and runoff in flood season have a certain positive correlation. c) Under the 63-year characteristic time scale, it can be predicted that the precipitation and runoff in the flood season of the source regions of the Yellow River will decrease in the next 5-10 years after 2020. [ABSTRACT FROM AUTHOR]

In order to deal with the complex evolutionary process of the “July 20” heavy rainfall disaster in Henan province and verify the scientific and effective emergency management measures, by using dynamic Bayesian network and applying evidence theory and emotional renewal mechanism, this paper proposed a scenario inference model which combined subjective and objective factors, and paid more attention to the research of decision-maker's emotion and other subjective factors. The results show that the dynamic Bayesian network can effectively simulate the dynamic process of scenario deduction, and the improved DS evidence theory can reduce the subjectivity of the model and deal with the uncertainty of the evolution process, the emotion renewal mechanism can effectively quantify the emotion change of decision-makers. [ABSTRACT FROM AUTHOR]

Aqueduct is a typical space thin-walled structure, which is very sensitive to external temperature changes. Surface insulation measures can effectively improve the temperature stress distribution of the structure and prevent surface cracks. Although the calculation method of surface insulation capacity commonly used in dam construction is of reference significance to aqueduct insulation issue, it cannot be directly applied, so the aqueduct insulation issue needs to be studied separately. Therefore, based on the temperature load of aqueduct structure, this paper put forward a calculation method of aqueduct insulation design based on the temperature and temperature stress analysis of concrete structure. The calculation results show that the stress state of the groove body can be greatly improved by laying 5.0 cm thick polyurethane foam insulation material on the outer surface of the straight wall section and the arc section of 0°-45°. When the temperature rises, the inner wall circumferential and longitudinal tensile stress does not appear. When the temperature drops, the circumferential and longitudinal stress of the outer wall is reduced, and the stress state of the inner and outer walls of the groove body meets the design requirements. The project case study shows that the calculation method of thermal insulation design proposed in this paper can be applied to the thermal insulation design of aqueduct during operation, and then the key parameters of thermal insulation design such as laying range and insulation layer thickness can be determined. [ABSTRACT FROM AUTHOR]

The water quality data of the river basin has dual dependencies in time and space. Based on the fact that most of the existing water quality prediction models are only based on the time dimension and cannot make effective use of the spatial correlation of water quality, a spatiotemporal prediction model based on graph convolution neural network GCN and long short-term memory network LSTM was proposed in this paper. Firstly, the whole watershed was constructed into the topology of station-to-station connection, and the distance along the river between stations was taken as the indicator of connectivity between stations. For each input time, an independent GCN was used to capture the spatial relationship between stations, and then the temporal variation characteristics were captured by LSTM. Finally, the multi-step prediction results were obtained by multi-layer perceptron (MLP). The south source of Qiantang River was selected as the research object, multi step prediction experiments were carried out on three water quality prediction tasks of pH, DO and CODMn at 15 monitoring stations in the basin. The results show that in the three water quality prediction tasks, the average percentage error MAPE of GCN-LSTM model compared with LSTM model is decreased by 15.29%, 11.77% and 9.8% respectively. Compared with some classical time series models, the model proposed in this paper can better capture the spatial relationship of watershed water quality, improve the accuracy of water quality prediction and provide a new method for watershed water environment quality prediction. The connections between monitoring points have differences, and using distance to represent the strength of the connections between monitoring points can make water quality prediction results more accurate. [ABSTRACT FROM AUTHOR]

The series consistency of the natural runoff of the Yellow River is affected by the changes in the substratum due to human activities, which makes it difficult to support the water allocation under the current conditions of the basin. In this paper, we took the Wuding River, a typical tributary in the middle reaches of the Yellow River, which has a significant reduction in the natural runoff, as an example, and used the Mann-Kendall test and the double cumulative curve method of annual precipitation and runoff to discriminate the consistency of natural runoff series, and used the correlation method of precipitation and runoff to carry out the consistent correction under the current conditions of the sub-base. The correction result shows that the multi-year average natural runoff volume in the current lower mat condition of the Baijiachuan section is 958 million m³, which is 193 million m³ less than that of the result of the "second survey", with a reduction of 16.8%. Extending the method of this paper to the Yellow River Basin, the analysis shows that the natural runoff in the Yellow River Basin is 49 billion m³, which is 15.5% less than the 58 billion m³ in the natural period, and 8.4% less than the 53.48 billion m³ in the "second survey" basin. [ABSTRACT FROM AUTHOR]

Steel pipe lining is a common support method for hydraulic engineering tunnels. It is very important to apply advanced technology to carry out void detection of steel pipe lining for project quality evaluation. In this paper, the longitudinal wave reflection coefficients of the three interfaces between steel and water, concrete and air were calculated, and the amplitude and phase variation characteristics of the reflection coefficients with the incident angle were analyzed. Through theoretical analysis, a data processing and analysis method by using the amplitude ratio of ultrasonic multiple reflection waves to detect voids was proposed. Concrete models with a thickness of 1.6 cm and 3.0 cm steel plates were made, and the models were tested with two types of 2.5 MHz probes. The results show that the reflected wave amplitude in the void area is relatively higher, which verifies the theoretical results of this paper. The pulse echo method is used for comparative detection, and the results show that the method has a certain detection effect. Since the actual impedance of the concrete cemented with the bottom of the steel plate is relatively lower, it is recommended to divide a larger detection unit for detection of a large amount of data to improve the accuraey of void discrimination.. [ABSTRACT FROM AUTHOR]

For measuring the effectiveness of a happy river building, searching the problems faced by a happy river building and exploring a new path for a happy river building within the framework of economic and social development, this paper explored the multi-level connotation of happiness through river ethics, Marxist view of happiness and Xi Jinping thought on ecological civilization. This paper, basing on analyzing the development direction and specific requirements of the modernization of the national governance system and governance capacity, focusing on the characteristics of social governance such as process, harmonization, diversity and interaction, simultaneously focusing on the modernization degree of governance system and governance capacity and governance effectiveness from the four perspectives of structure, process, function and service, built the evaluation index system of a happy river, which could provide a new method and path for comprehensive evaluation of regional water governance work from a broader perspective. [ABSTRACT FROM AUTHOR]

The coefficient of safety is an important index for the evaluation of slope stability. The safety coefficients calculated based on different instability criteria are significantly different, and the variability of the results will directly affect the evaluation of the stability state of slopes. In this paper, taking the step-type excavated slope of the Wanhuashan Trench Construction Project as the object, FLAC3D finite difference software was used to calculate the safety coefficient of loess slopes based on three different types of instability criteria, namely the calculation non-convergence criterion, the plastic penetration criterion and the displacement abruptness criterion, and to compare and analyze the differences, advantages and disadvantages of the evaluation results of the three criteria. The results of the study shows that there is a certain difference in the magnitude of safety coefficients obtained by using different instability criteria, with the order of magnitude being displacement abrupt change criterion > computational non-convergence criterion > plastic penetration criterion. The computational non-convergence criterion is easy to use and fast to solve, but does not show the change in the plastic zone of the slope during the discounting process. The plastic penetration criterion is not suitable as a criterion for slope instability on its own, but needs to be combined with the unbalanced force rate to be assessed, but it can show the area of shear damage and stretching of the slope. The sudden change of displacement criterion is tedious to solve, but the solution process truly reflects the critical damage state due to the change of slope displacement. For practical conditions such as loess slopes, it is recommended to use the fast computational non-convergence criterion to evaluate the slope stability in combination with the plastic zone penetration and the slope displacement change. [ABSTRACT FROM AUTHOR]

Based on J. Boussinesq's analytical formula of stress component at any point in the elastic half space under load, the spatial stress state of soil at any point was obtained and it was introduced into the settlement calculation model. A method of introducing confining pressure into the settlement calculation of remolded loess was proposed. The influence of three parameters including deviatoric stress, moisture content and confining pressure to the strain development of remolded loess was analyzed by stress loading triaxial test. The strain law of remolded loess under different parameters was obtained, and the settlement calculation formula of remolded loess strain affected by multiple parameters was put forward. Finally, the reliability of the formula was verified by engineering examples. The results show that the deviatoric stress, moisture content and confining pressure have a significant effect on the strain of remolded loess. The deviatoric stress and moisture content are positively correlated with the compressive deformation of remolded loess, while the confining pressure is negatively correlated with the compressive deformation of remolded loess. The empirical formula of remolded loess strain fitted by three parameters is effective. Through the engineering case verification of Shanxi Lyuliang Airport, the model settlement calculation results are basically consistent with the actual settlement monitoring results, indicating that the model in this paper can be more reasonably and conveniently applied to the settlement calculation and analysis of the remolded loess engineering site. [ABSTRACT FROM AUTHOR]

The strengthening of arch dam foundation is an important engineering measure to ensure the stability of dam abutment and the safety of arch dams. This paper took the reinforcement measures for the foundation of Dongzhuang arch dam as the research object, systematically simulated the discontinuity layer, mud fissures, wide joints and corresponding reinforcement measures of the dam abutment rock mass. The finite element analysis was conducted on the reinforcement effect of the dam foundation using elastic-plastic constitutive law. The calculation results indicate that the foundation reinforcement measures have little effect on the maximum displacement and stress of the dam body, but to some extent, they reduce the yield zone of the dam body and the foundation surface, improving the stress on the dam body. Through overload calculation and analysis, it is found that the foundation reinforcement measures have little effect on the plastic zone of the arch dam body, but the yield zone of the foundation surface is significantly reduced after the foundation reinforcement. The foundation reinforcement measures have a relatively smaller impact on the yield zone volume of fault f5 and muddy fissure Rnj3, but a significant impact on the yield zone volume of large fissure L22. In summary, the foundation reinforcement measures taken for Dongzhuang arch dam have improved the stress on the dam body and foundation, and improved the stability of the dam foundation. [ABSTRACT FROM AUTHOR]

In the process of agricultural water use, the negative benefits of water supply, water consumption, drainage and pollution collection will cause certain losses to the ecological economic system of agricultural water resources and then affect the sustainability of the system. Based on the negative benefits of the output of each link in the process of agricultural water consumption, this paper built an evaluation index system of loss degree of agricultural water resources eco-economic system. The economic loss rate, social instability rate and ecological load rate were used as indicators and the system loss rate was used as a comprehensive indicator. The energy method and AHP analytic hierarchy process were used to quantify the loss status and development trend of agricultural eco-economic system in Zhengzhou City from 2012 to 2017. The results show that during the study period, the economic loss rate of the agricultural eco-economic system in Zhengzhou is maintained at about 0.25% in 2012 to 2016, rising to 0.29% in 2017. The social instability rate is decreased from 21.46% in 2012 to 7.04% in 2017. The ecological load rate is basically stable at 11.7%, rising to 13.7% in 2017. The system loss is mainly affected by social instability rate and ecological load rate. The loss degree of the system as a whole shows a downward trend, from mild unsustainable to critical unsustainable and gradually tends to a benign development. [ABSTRACT FROM AUTHOR]

The basin ecological compensation can effectively solve the externality issues generated in the process of resources development and utilization, and it is of great significance in promoting the coordinated development of economy-society-ecology in the basin. Based on the evolutionary game theory, this paper analyzed the tripartite dynamic evolution scenarios of the higher government and the upper and lower local governments. Taking the Bosten Lake basin in Xinjiang as the research object, it set up a basin ecological compensation mechanism. The results indicate that only when the fines imposed by the higher government on the defaulting party are higher than the ecological protection costs and compensation fees in the upstream and downstream of the basin, the upstream and downstream can reach a stable equilibrium state of "protection" and "compensation" strategies. Based on the evolution results, the ecological compensation and ecological protection cost of Bosten Lake are 2.64×107 and 2.20×107 Yuan/year. Adopting the "compensation method for key pollution factors exceeding the standard" to determine penalty standards. The penalty standards based on exceeding the standard for CODM, NH3-N and TP pollutants are 1 312.51, 9 181.56 and 13 115.08 Yuan/t respectively. [ABSTRACT FROM AUTHOR]

Under the concept of ecological civilization building, how to realize the coordinated development of resources environment carrying capacity and economic development level in ecologically vulnerable regions have become one of the urgent issues to be solved in our country. This paper took 21 prefecture-level cities in the backward U-shape bend urban circle of the Yellow River, a typical ecologically fragile area as an example. Based on the resources environment and economic development data in 2005, 2010, 2015 and 2020, the entropy weight TOPSIS method was used to analyze the resources environment, and introduced the coupling coordination model to reveal the coupling coordination relationship and its spatial-temporal evolution patterns between resources environment carrying capacity and economic development level. The results show that the resources environment carrying capacity of the urban agglomeration of that area has a fluctuating upward trend with significant regional differences. The degree of coupling and coordination between resources environment carrying capacity and economic development level gradually tends to a higher degree of coupling as a whole. Through Moran index analysis, it is found that the resources environment carrying capacity and economic development level in the urban agglomeration of the backward U-shape bend of the Yellow River show a significant positive spatial correlation in terms of coupled coordination. [ABSTRACT FROM AUTHOR]

In order to effectively manage the groundwater, this paper provided a method of choosing the monitoring wells and determining controlled and assessed water level in over-exploitation areas from the perspective of regional and depression cone areas control. For the whole over-exploitation areas, Thiessen polygon method was used to assign control areas to each observation well, and the ratio of the control area of each well to the total area of the region was used as a weight to calculate the weighted average water level of the areas. Then, according to the proximity to the average water level, one regional water level of the controlled well was selected, regarding the water level of the controlled well at the end of the most recent normal year as the controlled and assessed water level. However, if the assessed year was a dry year, assessed water level should set slackness. For groundwater depression cone areas, it used the water level contour map to judge the distribution of the depression cone, and then chose a controlled well which was located near the center of the cone. Then, it similarly regarded the water level of the controlled well at the end of the most recent normal year as controlled and assessed water level. Applying this method to Guantao County, Hebei Province, the monitoring wells of W16 and W17 were selected as regional and depression cone areas of the controlled wells respectively. When the government had not formulated a plan for the water level recovery, the regional controlled water level was determined as 17.13 m. When the government had formulated a plan for the water level recovery (for example, the water level was recovered by 0.5 m within 5 years), the regional controlled water level was needed to increase by 0.1 m every year on the basis of 17.13 m. The assessed water level was equal to the controlled water level in wet and normal years, but the assessed water level in dry years was equal to the controlled water level minus 0.93 m (slackness). The controlled and assessed water levels in the depression cone areas were all determined to be 12.19 m. [ABSTRACT FROM AUTHOR]

In order to provide reference for the institutional construction of ecological protection and high-quality development in the Yellow River Basin, from a methodological perspective, this paper analyzed the new institutional construction needs for ecological protection and high-quality development in the Yellow River Basin, and the contradiction of the overall requirements of basin governance between fragmented management in reality. On the premise of adhering to ecological priority and green development, and implementing tailored and classified policies, the above issues could be solved by finding the smallest tool unit that covered both ecological protection and high-quality development. Green credit is the minimum common multiple between ecological protection and high-quality development. Establishing a green credit system through laws, regulations and policy regulations is a necessary foundation and logical starting point for basin collaborative governance. Yellow River Conservancy Commission and the nine provinces (regions) in the Yellow River Basin can, in accordance with higher-level laws and relevant policies such as the Yellow River Protection Law, promptly introduce operational norms applicable to the basin and region. [ABSTRACT FROM AUTHOR]

In order to provide scientific and technological support for the implementation of major national strategies for ecological protection and high-quality development and rural revitalization in the Yellow River Basin, this paper systematically summarized the research results, key technologies and typical models of the coordinated development of ecological governance and ecological economy in the Yellow River Basin over the years, analyzed the current existing and outstanding issues, and put forward corresponding countermeasures and suggestions. Over the years, various regions in the Yellow River Basin have explored a variety of coordinated development models of ecological governance and ecological economy for serious soil erosion. It includes the comprehensive ecological and economic management model with high adaptability of soil and water conservation-geomorphology-ecological economy, the ecological agriculture economic model of soil and water conservation, the integrated development model of soil and water conservation and ecological economy in wind-sand area, the coordinated development model of ecological management and derivative industries in Pisha sandstone area, the virtuous cycle model of rural energy ecology in semi-arid areas, and the governance model of ecological and economic belt of soil and water conservation in the Loess Plateau. At present, the existing outstanding issues include the concept of coordinated development of ecological governance and ecological economy is weak, the synergy between the two is not high, the space for coupling and coordination is unbalanced, and the development model has a single structure and low scale efficiency. The suggestions: To innovate the theory and key technologies of coordinated development of ecological governance and ecological economy; To establish a diversified investment mechanism, create a new model of coordinated development of ecological governance and economy and its production and industrial system with the goal of high-quality development, and explore the promotion mechanism and model of “full trust and full chain”; To build an appropriate technical system, industrial system, management system and talent support system; To establish a pilot demonstration county for the coordinated development of ecological governance and ecological economy, lead and optimize the coordinated development of regional modern ecological governance and economy. [ABSTRACT FROM AUTHOR]

In recent years, with the advantages of water saving, high efficiency and low cost, the self-suction dredging pipeline has gradually become one of the main measures for reservoir dredging projects. However, when the soil particles are fine and the silt has been deposited for a long time, its dredging effect decreases obviously. In order to explore the mechanism of breaking soil and influencing factors of sediment incipience, model test method was adopted in this paper. A cohesive sediment sample was prepared by negative pressure consolidation, and then the vertical submerged jet experiment with different jet velocity, jet spray nozzle size and jet target distance was carried out. The experimental results show that the erosion breaking mechanism of the cohesive soil sample is quite different from that of the non-cohesive soil due to the existence of viscosity. The development process of the scour hole has certain randomness and self-similarity. The erosion efficiency of the jet flow is proportional to the jet velocity and the Jet spray nozzle size, and inversely proportional to the jet standoff distance. At the same time, the jet target distance has the most obvious influence to the shape of scour holes. [ABSTRACT FROM AUTHOR]

In view of the fact that there are many majors in water conservancy and hydropower engineering, the difference of modeling tools will lead to the difficulty of data transfer and even data loss when professional collaboration or phased results are transferred. This paper innovatively proposed to extend the original IFC (Industry Foundation Class) data structure on demand, established the extended data structure method of digital twin water conservancy and hydropower engineering, and formed the extended IFC expression method of water conservancy and hydropower engineering for semantic expression, geometric expression and attribute set expression, so as to provide standardized storage space for the easily lost data in water conservancy and hydropower engineering. On this basis, based on Autodesk Revit software, with the help of Revit IFC Exporter open source toolkit, the extended IFC export function including geometric information and attribute information was developed, and the dam structure was extended and exported, which verified the operability of the extended data structure establishment method. Finally, through the data transfer case, it is proved that the method can effectively ensure that the engineering information is not lost during the transfer process. [ABSTRACT FROM AUTHOR]

Using the vertical pipe test data of riverbed sediment in the downstream section of the main stream of Hotan River, the paper carried out the application and evaluation of different vertical pipe test parameter calculation methods. The HTST01 test point was selected for vertical permeability test, and the HTST02 test point was selected for horizontal and vertical permeability tests, respectively. The rationality of the permeability coefficient value obtained by the traditional calculation method and the difference between its calculation results and the linear graphical method were analyzed. The results indicate that: the array of permeability coefficients obtained by traditional calculation methods approximately follows a non-standard normal distribution with certain skewness and kurtosis, all of which have moderate variability. The use of arithmetic mean values for parameter values has certain rationality and applicability. When using random calculation values, the error size of parameter values has contingency and uncertainty. The straight line graphical method can effectively avoid the generation of random errors, but the calculation results obtained by it differ from the arithmetic mean of traditional calculation methods to some extent. The average relative error value is 10.59%, and the maximum relative error value exceeds 27.00%. In the application process of vertical pipe tests, the influence of the rationality of parameter values obtained by calculation methods should not be ignored. [ABSTRACT FROM AUTHOR]

In order to improve the incongruity issue（in the time dimension） of water supply and demand of Hongsibu water pumping system. Taking the water demand process line and the design flow line of pumping station as the comparison object, this paper analyzed the difference between the demand flow and the design flow of pumping station caused by factors such as the irrigation area, the proportion of efficient water-saving area and irrigation quota（fixed value） at different time periods in the pumping irrigation area, and built the optimization regulation model of water supply flow and irrigation demand flow of pumping station in the multi-stage pumping system of Hongshibu. Based on the water demand process line multi-stage pumping station water supply and demand optimization scheduling model, including flow balance model, water demand process line model and flow regulation model, the simulation analysis of four working conditions in Hongshibu irrigation area show that when the high-efficiency water-saving area accounts for 60%, as the irrigation area increases from 6.02×104 hm² to 6.77×104 hm², the regulated flow in the controlled irrigation area of Hongsan Pumping Station gradually increases, that is, the regulated storage capacity increases from 1.47 ×106 m³ to 8.49×106 m³, while the regulated storage scale of the other three pumping stations basically remains unchanged. When the high-efficiency water-saving area accounts for 80%, there is basically no need for regulation and storage at Hongyi Pumping Station and Hongsan Pumping Station, while the regulated flow at Hongsi Pumping Station and Hongwu Pumping Station maintains a constant value, and the regulation and storage scales are 3.08×106 m³ and 0.47 ×106 m³ respectively. The water supply and demand optimization scheduling model of multi-stage pumping station based on water demand process line is simple to build and apply. The model can better reflect the water distribution relationship between the construction of multi-stage pumping station and the branch lines of pumping station, and the adjustment period and allocation flow are flexible, which can be suitable for the water supply system of multi-stage pumping station with different storage demand. [ABSTRACT FROM AUTHOR]

In order to evaluate the sustainable utilization level of water resources in the nine provinces (autonomous regions) of the Yellow River Basin, improve the status of water resources and realize the sustainable utilization of regional water resources, this paper proposed a comprehensive evaluation index of sustainable utilization of water resources suitable for the nine provinces (autonomous regions) of the Yellow River Basin based on the water footprint model. Spearman correlation analysis and multiple linear regression analysis were used to analyze the driving factors of sustainable water resources utilization in the nine provinces of the Yellow River Basin. The results show that the water resources footprint of the nine provinces (autonomous regions) in the Yellow River Basin from 2010 to 2020 increases first and then decreases in a small amplitude, and the water environment footprint shows a decreasing trend, and the spatial distribution of water resources footprint and water environment footprint is very uneven. In the nine provinces (autonomous regions) of the Yellow River Basin, the level of sustainable utilization of water resources has increased to different degrees. The level of sustainable utilization of water resources in the upstream provinces (autonomous regions) is higher, while the level of sustainable utilization in the middle and downstream provinces (autonomous regions) is lower. The main driving factors of sustainable water resources use are population density, wastewater treatment rate and the proportion of secondary industry, followed by per capita water consumption and fertilizer application intensity. [ABSTRACT FROM AUTHOR]

In order to investigate the dynamic evolution and regional differences of quaternity cooperation of water resources-ecology-city-industry in the Yellow River Basin, the paper adopted the synergy model, kernel density estimation, Dagum gini coefficient and its decomposition to estimate it based on the data of 76 major prefecture-level cities in the Yellow River Basin from 2016 to 2020. The results show that the number of cities in primary, intermediate and good coordination is 30, 33 and 13 respectively. The level of synergy among cities is on the rise, but the absolute difference between cities is expanding and the relative difference is narrowing. except for Hu-Bao-E-Yu urban agglomeration, the absolute difference of the coordination degree of the other six urban agglomerations all shows an expanding trend. The internal differences between the upper and lower reaches of the Yellow River show a downward trend, while the internal differences in the middle reaches show an upward trend. The difference between the upper and middle reaches is the largest, and it shows a further expansion trend, and the difference between the upper and lower reaches is gradually narrowing. The difference in Hu-Bao-E-Yu urban agglomeration is the smallest and the difference in Guanzhong urban agglomeration is the largest. The difference between Guanzhong urban agglomeration and Shandong peninsula urban agglomeration is the smallest, and the difference between Jinzhong urban agglomeration and Shandong peninsula urban agglomeration is the largest. In the future, we should further strengthen factor coordination and regional coordination, give play to the dynamic comparative advantages of various regions, and promote the in-depth implementation of ecological protection and high-quality development strategies according to local conditions in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

Exploring the particle size distribution of suspended load and bed material load in river channels helps to analyze the overall sedimentation situation of river sediment and provide feedback to guide the optimization of reservoir operation. In order to systematically grasp the distribution pattern of suspended load and bed material load particle size in the lower Yellow River, this paper collected and organized the water and sediment series data from 6 key sections such as Huayuankou in the lower Yellow River. Recursive feature elimination algorithm was used for variable selection, and a prediction model for sediment particle size in the lower Yellow River was built based on different machine learning algorithms. The results show that the variable selection algorithm can effectively extract the main influencing factors in the model, and when using machine learning models to predict the sediment particle size of different sections, the overall performance is good on the test set. The R² values of suspended load and bed material load particle size prediction under each section optimization model are between 0.64 and 0.89, and 0.37 and 0.72 respectively. At the same time, when using 2020 data to further verify the predictive effect of the model, the predicted and actual values of suspended load and bed material load particle sizes R² are also up to 0.609 7 and 0.445 6 respectively, which indicates that the built model can effectively achieve the prediction of sediment particle sizes in the lower Yellow River channel. [ABSTRACT FROM AUTHOR]

How to utilize the joint operation of reservoir groups to maximize sediment discharge efficiency is a key technical challenge in water and sediment regulation. This paper selected the joint operation of Sanmenxia and Xiaolangdi reservoirs in the period of water and sediment regulation in 2023 as the object, analyzed the water and sediment processes of the two reservoirs under different matching opportunities and matching water levels, and quantified the water and sediment regulation effect under different matching opportunities and matching water levels between the two reservoirs. Although the Sanmenxia Reservoir has a smaller water storage capacity and limited water transfer capacity, by changing the discharge time of the reservoir, the scouring effect of Xiaolangdi Reservoir is quite different. As the matching water level decreases, the amount of erosion in the reservoir area gradually increases. With the delay of the relative discharge time of Sanmenxia Reservoir, the erosion amount in the reservoir area shows a trend of first increasing and then decreasing. [ABSTRACT FROM AUTHOR]

This paper focused on analyzing the runoff characteristics of the Yellow River source area during the late-flood season, based on the data of Tangnaihe Station from 1956 to 2022 by using mathematical and statistical methods. Combined with the full-load power generation flow of Longyangxia Reservoir, the water storage capacity of Longyangxia Reservoir in the post-flood period was analyzed and discussed in different scenarios. The results show that a) the inter-annual variation of the late-flood runoff at Tangnaihai Station is significant, with uneven abundance and predominantly normal parity, accounting for 29.1% of the flood runoff. b) The average runoff volume above 1 000 m³/s during the late-flood season at the station is 896 million m³, with greater inter-annual variation. And applying with 1 000 m³/s power generation flow to meet the guarantee rate of Longyangxia Reservoir storage to the normal storage level is only 10%, and the water level at the end of the flood season cannot reach to the normal storage level of 2 600 m. Thus, it is suggested to adjust the time of entering the post-flood season according to the incoming water in the later period, optimize and adjust the annual operation scheme of Longyangxia Reservoir, and lay a foundation for efficient and reasonable utilization of the late-flood season water resources in the source area of the Yellow River. [ABSTRACT FROM AUTHOR]

The important feature of resettlement work is that it has a strong policy nature. Under the background of rural revitalization strategy, it is necessary to integrate resettlement work into the requirements of rural revitalization with prosperous industry, livable ecology, civilized rural style, effective governance and rich life. The two complement each other and develop at the same time. Based on the background of rural revitalization and the perspective of rural revitalization, this paper examined the particularity of the resettlement mode of Jiufengshan Pumped Storage Power Station and put forward a new resettlement mode of land acquisition and resettlement of the station of “suitable for relocation + suitable for production + suitable for beauty + suitable for living + civilization”. It is not only conducive to the completion of resettlement tasks, but also promotes the implementation of rural revitalization policy. It can be accumulated case experience for the follow-up large-scale land acquisition and resettlement of pumped storage power station construction projects in Henan Province. [ABSTRACT FROM AUTHOR]

Xinjiang, located in the arid region of the northwest, is an important agricultural province and water resources are an important guarantee and a necessary condition for the development of local agriculture. Taking Shache irrigation area of Xinjiang as an example, this paper discussed the possibility of promoting the sustainable development of agricultural economy in the irrigation area by optimizing the crop planting structure and rationally using water resources according to the “14th Five-Year Plan” for Kashgar region and the outline planning document for the long-term goals in 2035. Specifically, from the three perspectives of agricultural ecological benefits, economic benefits and irrigation water consumption, the multi-objective comprehensive optimization model was built in this research to adjust and analyze the crop planting structure in Shache irrigation area. The results show that a) the optimization of crop planting structure in the current year can increase carbon sequestration by 0.8 t, economic benefits by 584 538 800 Yuan and save 1 110 200 m³ of total agricultural irrigation water. b) After the multi-objective planning of the crop planting area in 2025 and 2035, the ecological and economic benefits will be greatly improved, the water saving effect will be remarkable and the purpose of adjusting the crop planting structure will be achieved. [ABSTRACT FROM AUTHOR]

In order to expedite the transition of the Yellow River Simulator into the operational phase and quickly make use of its positive role in the difficulties of water resources shortage, economic imbalance and ecological fragility in the Yellow River Basin, an intelligent calculation method system for the Yellow River Simulator had been thoroughly sorted out and implemented. Drawing upon the concept of intelligent computing, the vital importance of the Yellow River Simulator’s intelligent computing was articulated from the perspectives of data storage and preprocessing, simulation computing power, and swift responsiveness, as well as its significance in ecological conservation and management, efficient water resources utilization and disaster evaluation and mitigation. Based on the architectural framework of the Yellow River Simulator, four branches of intelligent computing methods, namely biomimetic intelligent computing, machine learning, fuzzy computing and intelligent computation were summarized in detail. Envisioning the transformative potential of intelligent computation methodologies for the Yellow River Simulator, this paper explored its huge application prospects in development planning, disaster management and resources allocation. [ABSTRACT FROM AUTHOR]

Cities are the spatial carriers of ecological protection and high-quality development in the Yellow River Basin’s nine provinces（regions). With the help of eco-efficiency, we can reveal the coordinated development of ecology and economy. In the existing studies, urban eco-efficiency is usually measured under the same external conditions, but little consideration is given to the differences of cities. By constructing a three-stage super-efficiency SBM model after excluding external environmental factors, this paper calculated the ecological efficiency of 57 cities in nine provinces（regions） of the Yellow River Basin from 2010 to 2019, and further analyzed the spatial-temporal differentiation characteristics of urban ecological efficiency in nine provinces（regions） of the Yellow River. The results show that compared with the traditional super-efficiency SBM model, the three-stage super-efficiency SBM model is more reasonable. After excluding the influence of environmental variables such as income level, industrial structure, environmental policy and foreign direct investment, the urban eco-efficiency of nine provinces（regions） in the Yellow River Basin decreases slightly. In terms of time evolution characteristics, the eco-efficiency value of most cities in the nine provinces（regions） of the Yellow River Basin shows a fluctuating downward trend, and the eco-efficiency of cities in the upper reaches decreases significantly. In terms of spatial distribution characteristics, most cities in the nine provinces（regions） of the Yellow River Basin are concentrated in low eco-efficiency areas, showing an alternating spatial distribution trend of “low-high-low-high” from west to east. [ABSTRACT FROM AUTHOR]

The interaction between water resources utilization and urban development in urban agglomerations in the Yellow River Basin is the key to the high-quality development of urban agglomerations in the basin. There is an urgent need to explore the coupling and coordination relationship between the two under the sustainable development goals, and provide new ideas for exploring the collaborative mechanism of ecological protection and high-quality development of urban agglomerations in the Yellow River Basin. Taking 72 cities and five urban agglomerations in the Yellow River Basin as examples, this paper established an analysis framework for the coupling of water footprint and city development index in 2010-2019 according to the sustainable development goal proposed by the United Nations and the difference of water resources utilization. The Theil variation index method was used to evaluate the spatial differences in coupling coordination results. The results show that the water footprint is decreasing year by year and the city development index is increasing year by year. The coupling relationship between water footprint and city development index is in an unstable state of “rising-falling-rising”. The difference in the level of urban water resources utilization within the urban agglomeration is the main reason for the difference in the level of development, and there are significant differences in the coordination relationship between water resources utilization and urban development in different urban agglomeration development stages. It suggested to build a trans-regional water resources co-governance system, give full play to the regulatory role of public water resources policies in urban agglomerations, and systematically plan the safety pattern of aquatic environment protection and water resources development and utilization among urban agglomerations. [ABSTRACT FROM AUTHOR]

There are great distances between the embankments from Baihezhen to Taochengpu in the Yellow River where historically erosion and deposition of the channel had been changed rapidly and the river is in the wandering and varying regime. After years of improvement, the river regime has been basically controlled on the whole and the channel has gradually become stabilized. Under these conditions, in order to promote the ecological protection of the Yellow River and the development of floodplain areas, upgrade the level of river management, the river was simply divided into channel and floodplain. This paper proposed the concept of channel alignment for the first time, provided the definition and the principle of alignment setting, emphasized that establishing the channel alignment should take the safety of flood control as the premise, explained setting methods and on-site marking methods and also analyzed the functions of channel alignment. [ABSTRACT FROM AUTHOR]

In order to clarify the current situation of digital economy and high-quality development in the Yellow River Basin, explore the coupling coordination and interaction between these two aspects and provide a reference for implementing ecological protection and high-quality development strategies in the Yellow River Basin, the interactive mechanism between digital economy and high-quality development in the Yellow River Basin was analyzed theoretically. Based on the panel data 2011 to 2020, a total of 64 prefecture-level cities in the Yellow River Basin were selected. This paper measured the development level of the digital economy and high-quality development level, empirically examined the coupling coordination relationship between these two dimensions by using coupling coordination degree model and explored the interactive relationship between the two through a PVAR model. The results of the study show that a) the development level of the digital economy in the Yellow River Basin has shown improvement during the research period, however, it remains generally lower with significant regional differences, which forms a circle distribution pattern with Jinan, Zhengzhou, Xi’an, Taiyuan and Hohhot as the core cities, and has the spatial distribution characteristics of high in the east and low in the west. b) The imbalance of high-quality development in the Yellow River Basin is prominent, characterized by the polarization and a distinct circle structure. This has resulted in the formation of a high-value area with Jinan, Zhengzhou, Taiyuan, Xi’an, Lanzhou and other provincial capitals as the core cities. c) The coupling coordination degree between the digital economy and high-quality development in the Yellow River Basin has been increasing annually, but the overall coordination level remains insufficient. The current implementation only achieves the transition from the mild imbalance to near imbalance levels, and the coordination degree also illustrates a pattern of lower reaches＞middle reaches＞upper reaches. d) Both the digital economy and high-quality development in the Yellow River Basin are characterized by self-reliance. High-quality development plays a significant role in promoting the digital economy, while the role of the digital economy in enhancing high-quality development needs to be reinforced. [ABSTRACT FROM AUTHOR]

Increasing carbon productivity is an effective means to achieve carbon peak and carbon neutrality. To coordinate the relationship between economic growth and carbon emissions reduction in the Yellow River Basin, the carbon productivity of 9 provinces（regions） in the Yellow River Basin from 2007 to 2017 is calculated. Based on DEA-Malmquist’s total factor carbon productivity model, the spatiotemporal evolution trajectory and spatial distribution pattern of total factor carbon productivity of 9 provinces（regions） is deduced. The potential improvement space of total factor carbon productivity is scientifically decomposed and the influencing factors of the spatiotemporal evolution of carbon productivity is identified. Based on this, the improvement path of carbon productivity in the Yellow River Basin is condensed. The results show that, 1) in the time dimension, the carbon productivity of 9 provinces（regions） rise steadily with the growth of per capita GDP,an increase of 283.3%, while the total factor carbon productivity remains at around 1.000. 2) In the spatial dimension, the regional heterogeneity of carbon productivity and total factor carbon productivity is relatively large affected by economic development and resource endowments, showing a spatial evolution pattern of “downstream significantly higher than midstream, and midstream slightly higher than upstream”. 3) From the point of influencing factors, the midstream and upstream belong to technical efficiency-driven, the role of technological progress is weak, while the downstream is a co-promotion type of technological progress and technological efficiency. Based on this, this paper proposes strategic suggestions such as innovating institutional mechanisms, promoting low-carbon development models, focusing on lowcarbon technology innovation, accelerating energy structure adjustment, strengthening regional integration cooperation, and improving factor allocation efficiency. [ABSTRACT FROM AUTHOR]

Xiaolangdi Reservoir is the key project of flood control and security in the lower reaches of the Yellow River, and the sediment retention period of the reservoir is the most significant period for flood control and sediment reduction benefits. This paper analyzed the new requirements for flood control and security of Xiaolangdi Reservoir under the new situation of the lower reaches of the Yellow River, and pointed out that it was of great strategic significance to extend the sediment retention period of Xiaolangdi Reservoir as much as possible, so as to maintain the effective storage capacity of the reservoir as long as possible, especially the flood control storage capacity. The research shows that the larger reservoir capacity has a strong ability to deal with large floods, which is conducive to the prevention of “black swan” events; after the flood control operation of the reservoir, the loss of the beach storage capacity is small, which is conducive to the long-term maintenance of the reservoir’s strong flood control capacity; the combination of sediment storage capacity and water and sediment regulation capacity can significantly enhance the vitality of water and sediment regulation, and create storage conditions for the Guxian Reservoir to exert the overall joint force of the water and sediment regulation system after putting into operation; the use of the sediment storage capacity for flood control in the downstream beach area is conducive to improving the flood control standard of the beach area and reducing the loss of the beach area in the normal flooding. Optimizing the operation mode of reservoir operation, implementing reservoir dredging and building Guxian Water Control Project as soon as possible are important measures to extend the sediment retention period of Xiaolangdi Reservoir. [ABSTRACT FROM AUTHOR]

In order to reveal the annual variation of the distribution of water, heat and salt in the dry soil in the gullied rolling loess area after continuous mulching for many years and provide reference for further research on improving the water, heat and salt status of dry layer soil, the paper took jujube woodland that covering with the white film (colorless transparent plastic film), black film (black bovine felt) and bared ground control test plots continuously for 5 years in Mizhi County, Northern Shaanxi Province as the research object, the paper analyzed the migration and changes of water, temperature and salt in different soil layers during the year based on the location monitoring data of soil water content, temperature and conductivity by GS3 sensors with buried depths of 5, 15, 30, 50, 75, 100, 125 and 150 cm. The results show that a) after continuous film mulching for 5 years, the water content of 0-150 cm soil layer is significantly higher than that of bared soil, especially the water storage of 0-60 cm soil layer is significantly increased, and the black film mulching has a better effect on rain collection and water conservation than that of the white film mulching. b) The soil temperature in each soil layer of the two mulching plots is significantly higher than that of the bared plots. The white film mulching has a better thermal insulation effect in the cold period, and the black film mulching has a certain regulatory effect on the soil temperature in the 0-60 cm tilling layer in the high temperature period. c) After many years of film mulching, the phenomenon of surface soil salt accumulation will occur, but it will not cause soil secondary salinization. d) There is a significant positive correlation between soil water and salt in each plot at different stages, and the correlation between water and salt is relatively weaker in the plot covered with black film, while the correlation between soil water and heat and salt is significantly different. The two kinds of film mulch have different regulatory effects on soil water, heat and salt at different stages. [ABSTRACT FROM AUTHOR]